What drought? New device from MIT pulls drinking water out of thin air

While there’s no imminent drinking water crisis in the U.S., technology like this can be helpful abroad – Anthony

Powered only by solar energy, a new device developed at MIT could provide relief to regions where water is scarce.

A device developed by Evelyn Wang, professor of mechanical engineering at MIT, harvests clean drinking water from vapor in the air, even in arid conditions.

With droughts plaguing much of the western United States and millions of people across the globe living without access to safe water, the need for technologies that produce clean water is greater than ever. The key, according to Evelyn Wang, the Gail E. Kendall Professor and department head for MIT’s Department of Mechanical Engineering, is in the very air we breathe.

“Water vapor is all around us in the air, even in arid conditions,” explains Wang. She and her team in MIT’s Device Research Laboratory have developed a device that can tap into this abundant resource and literally pull water out of thin air.

The key to the process is a powder that desiccates the air, attracting vapor directly to the porous matrix at the base of the device’s main chamber like a sponge. The vapor is then condensed into liquid and can be collected as usable water – even in dry atmospheres with as low as 20 percent humidity.

The entire process of converting the water vapor found in air into potable water can be done using only the power of the sun. “The device is completely passive,” says Wang. “There is no need to use outside power supplies which can help keep the device low-cost and efficient.”

Keeping costs low and efficiency high is one of Wang’s central goals. “We hope to develop a device that provides relief to the millions of people living in communities that lack the infrastructure needed to provide access to clean drinking water or those living in regions plagued by drought,” adds Wang.

During a field test in Tempe, Arizona earlier this year, a small proof-of-concept prototype of the device extracted a quarter-liter of water per day per kilogram of the absorbent powder. The researchers hope to increase this output by further tailoring the powder and optimizing the device.

If the production capacity of the device can be increased, Wang’s research could have a tangible impact in places experiencing water scarcity — even in the driest of conditions.

Post navigation

if used in the quantity needed, this device would increase the arid areas..

Vote Up3Vote Down

July 23, 2018 9:06 am

Drew

Measuarbly drying the air with this device , even thousands of these, is equivalent to draining Lake Erie with a soup ladle…

Vote Up3Vote Down

July 23, 2018 9:27 am

Tom S.

This device is not intended as a bulk collector for irrigation. It is water for people and maybe livestock. The amount of water it would remove would be a drop in the bucket (only from the air it interacts with, not the kilometers of air around and above it). Trying to find a cloud in the silver lining?

Vote Up4Vote Down

July 23, 2018 9:36 am

rocketscientist

I’m attempting to find even any silver tarnish smudges or any traces of benefit on that cloud.
This doesn’t promote itself as better than condensation cycle. If it is more energy dependent then it is not better.
What reason is forcing somebody to attempt to raise livestock in a desert, or consider it a good idea?
These are the questions we should be asking, not how to enable somebody to act stupidly.

“Just because you can, doesn’t mean that you should.”

Vote Up2Vote Down

July 23, 2018 10:09 am

rocketscientist

After some further investigation to this scheme I am embarrassed for my alma mater.
This is one of the most frivolous concepts ever conceived.

The concept of a solar still is very very old. Why not simply steam the rocks in the desert to get their moisture.

Vote Up2Vote Down

July 23, 2018 10:26 am

Ben of Houston

You would need vast quantities of this to make enough even to make enough for that soup ladle. As a proof of concept, it’s entirely unimpressive.

Vote Up2Vote Down

July 23, 2018 10:11 am

rocketscientist

Ostensibly the water extracted would be consumed locally, hence returned to the local atmosphere. It may end up needing processing to remove the solid and mineral content, which atmospheric evaporation does does fine, although the wind direction will effect property values. Most of the evaporated moisture won’t be recovered locally and therefore most of it would be going down wind to someone else’s collection zone. But, the moisture that was originally collected from the air had blown in form elsewhere as well.
I think I’ve just described the basic water cycle.
In space craft we call it the water recycling system, and humidity aboard the International Space Station (ISS) is a big deal. Atmospheric systems (Russian design/built) scrub the air, and recycle biologic wastes. Water is worth more than gold in space.
Here on earth its no different. If its not a newly created water molecule (from egads! combustion) it has been cycled through numerous alimentary tracts long before some eco-loon declares it clean.

Vote Up0Vote Down

July 23, 2018 4:23 pm

wesley bruce

Most air wells are drawing on indoor air, recapturing the humidity from sweat, breath and indoor plants.

A farm air well would only lower the humidity 1 or 2 %, at night generally, and if used locally on crops and livestock the humidity would be restored as they transpire, break or sweat. So no net change but crops and livestock gets watered. The farm air well would exhaust dry air out a tall chimney to get the dry air clear of the intakes.

Vote Up2Vote Down

July 23, 2018 9:06 pm

commieBob

If you pull water out of the air, the already parched land will give up its moisture all the more quickly. I suspect that if you pull out enough water for irrigation, the net result will be worse.

If you’re going to farm in arid conditions, you’re better off changing the way you farm. link

Vote Up8Vote Down

July 23, 2018 9:09 am

rbabcock

Just what we need, a device to drop the global relative humidity and bring on another ice age. Less WV in the atmosphere means less heat stored. Then throw in increased evaporation by the oceans into drier air, which causes ocean skin cooling.

Sounds like someone needs a grant or two to figure all this out before we commit to this on a grand scale.

I have a lot of time on my hands so I volunteer. Sounds like a lot of world travel to nice resort areas.

“Just what we need, a device to drop the global relative humidity and bring on another ice age. “
No. Just as you can’t achieve a long term increase in humidity by letting off steam, so you can’t achieve a long term increase in aridity. There is an ongoing dynamic equilibrium where about 1 ton water/m2/year (spatial average) evaporates from sea, condenses and falls as rain. Trying to dry the air just leads to more evaporation. Trying to moisten it just makes more rain.

Vote Up-4Vote Down

July 23, 2018 9:45 am

Curious George

Nick, extracting water from the air is different in Sahara and in Amazonia. This device could be useful in humid conditions, provided there is enough sunshine.

Vote Up0Vote Down

July 23, 2018 9:51 am

rocketscientist

In areas with high humidity, availability of water is not an issue. Clean drinking water is totally different and is a function of sanitation not availability.

Amazonians don’t need active dehumidifiers to create water.

Vote Up0Vote Down

July 23, 2018 10:33 am

Bryan A

Excepting that the device should produce Clean Water and not contaminated water, the size necessary to produce enough clean water for a single person would make it unwieldy for survival

Vote Up2Vote Down

July 23, 2018 2:21 pm

rocketscientist

True, the device will only produce clean water, however that water must be collected into something and once it is exposed to the air and whatever container it is distributed from it is only as clean as the dirtiest part.

BTW solar stills are basic devices in many life rafts.
I might suspect a personal-sized life support system could be adapted for extreme environments.

Vote Up1Vote Down

July 23, 2018 4:33 pm

Thomas Homer

Nick Stokes: “There is an ongoing dynamic equilibrium … Trying to dry the air just leads to more evaporation. Trying to moisten it just makes more rain.”

Did you just describe the mechanism which precludes any potential ‘runaway’ climate change?

No, It’s the mechanism responsible for positive water vapor feedback. The equilibrium has large shifts of wv each way, and there isn’t much point in trying to add or subtract from them to change RH. But temperature can shift the equilibrium point, which is a sustained change.

Vote Up-4Vote Down

July 23, 2018 11:41 am

Thomas Homer

Nick Stokes: “The equilibrium has large shifts … each way”

Equilibrium: a state of rest or balance. So it’s a volatile equilibrium?

Of course, once you have introduced a contradiction you can derive any conclusion. That’s awfully convenient for you.

Vote Up3Vote Down

July 23, 2018 12:02 pm

Alasdair

Yes nature hunts around this gravity/water temperature global provile in a chaotic way . We have to live with that.

” a dynamic equilibrium exists once a reversible reaction ceases to change its ratio of reactants/products, but substances move between the chemicals at an equal rate, meaning there is no net change”

I don’t see a reference to a state of rest that also has wild swings in either direction.

Care to clarify? A state of rest in unrest?

Vote Up0Vote Down

July 24, 2018 8:24 am

MarkW

The only problem is that actual science has not been able to find any evidence to support the notion that relative humidity stays the same regardless of temperature. This is why all of the climate models run way hot. They assume a positive feedback that doesn’t exist.

Vote Up6Vote Down

July 23, 2018 12:45 pm

Alasdair

Quite: The feedback is negative, as somewhat roughly described above.

Vote Up2Vote Down

July 23, 2018 1:34 pm

Alasdair

Sorry Nick but you are wrong here. The process is as follows:
Gravity generates the pressure. This pressure dictates the temperature at which the vapour pressure of water commences evaporation (phase change) at zero relative humidity. The relative humidity (aka concentration in ppm) increases to the balance point where the Partial Pressure of the water equals the Vapour Pressure. At this point evaporation only continues if the gaseous water is removed at the same rate as the evaporation. This is achieved by the buoyancy of the water which rises up through the atmosphere and dissipates heat on the way up to space.
The temperature at which this happens is function of pressure where additional heat input only increases the rate of evaporation not the temperature.
Water vapour feedback is very negative in this situation and acts as the global thermostat.
If you want confirmation of this try boiling your kettle above 100C at sea level. OK that is just one point on the curve but its true for other pressures but of course at different temperatures.

Alasdair“Gravity generates the pressure. This pressure dictates the temperature at which the vapour pressure of water commences evaporation (phase change) at zero relative humidity.”
That makes no sense at all. At zero relative humidity water will commence evaporation at any temperature (compatible with liquid water) or pressure.

“If you want confirmation of this try boiling your kettle above 100C at sea level.”
This makes no sense here either. No boiling is involved in the terrestrial water cycle. 100C is the temperature at which steam bubbles can form below the surface (vap press=1 atm), which of course greatly accelerates evaporation. It responds to absolute pressure, whereas normal evaporation depends on the partial pressure of water only.

Vote Up-2Vote Down

July 23, 2018 4:37 pm

getitright

did you mean 1 ton or did you infer to mean 1 tonne.
The former would be mixed metrics. (pun intended)

Right out of Frank Herbert’s “Dune”. This will become a key preppers device. A few thoughts:

I’d like to get a metric: grams/H2O/hour/device kilograms as a function of temperature and humidity.

I’d like to suggest the use of silver in the device to deter bacterial fouling.

Vote Up2Vote Down

July 23, 2018 9:30 am

Donald Kasper

Bluegreen algae and mold, oh yeah. And spores. This gonna smell in short order. And the chemical will leach into the water and cause health problems.

Vote Up0Vote Down

July 23, 2018 12:35 pm

MarkW

They’ve reinvented the de-humidifier!!

Vote Up6Vote Down

July 23, 2018 9:36 am

rocketscientist

My thoughts as well, only they seem to have created a more complex dehumidifier. One that needs 8 kg of powder working for each human just to meet the daily drinking needs.

Maybe everybody will just need to lug around back-pack with a water reclamation system for their personal needs. Lets combine these into a functional garment that can be worn when going outside.
…Stillsuits from Dune.

Vote Up7Vote Down

July 23, 2018 9:56 am

rocketscientist

There is no mention on how much energy this device uses to extract the moisture from the absorbent powder.
I don’t imagine this powder will willingly cede its recently gotten gains as it is specifically intended to absorb water.
Unless this new process is any more efficient than the tried and tested condensation cycle, what have they created that is of any real use?

Such a process would only be valuable for sustaining living conditions in an already inhospitable climate. If reliance for such systems were to become required for habitation in these regions, then continued habitation in those spots is dependent on availability of energy.
One can see evidence of such occurrences with today’s environmental control technologies. In large urban heat islands built in regions where habitability is dependent on indoor temperature control, large portions of the population are placed into distress when the power systems are inadequate to supply the required demand.

Vote Up3Vote Down

July 23, 2018 9:41 am

jorgekafkazar

“There is no mention on how much energy this device uses to extract the moisture from the absorbent powder.”

It is traditional in academia never to provide any numbers that could reveal in seconds the utter bogosity of the underlying concept.

Vote Up1Vote Down

July 23, 2018 11:29 am

Red94ViperRT10

I’m not worried about desiccating a desert. Even if she can get the efficiency she wants, the water removed from the air will be consumed by the intrepid explorer and promptly returned to the surrounding environment through exhalations, sweat and urine. But what has been described is a long way from ready for prime time. At 0.25 liter/kg/day (that’s not a lot), that means each explorer needs, what, another commenter said 8 kg/person, (that’s only slightly more than 4 cups a day, is that enough to keep a person alive?) that is quite a mass to lug around (another commenter got as high as 20 kg, I can’t argue, they may be righter than I). The press release says, “…condensed out…”… I’m baffled, if it is condensed out there’s no need for the powder, just condense it directly out of the air (repeat of another comment, apparently). Maybe I’m just being facetious and they’re talking about a desiccant (the video verifies, it’s a desiccant), but I could be wrong. How much energy is needed to cause the desiccant to give up the water (the video was no help in this regard, I think the Cliff Notes version says, “at this point a miracle occurs)? And how will that energy be provided? The press release said it could be done using only the power of the sun. So now we have 8 kg of magic powder and a solar collector the size of a barn door? Or just leave the jug (large enough to hold 8 kg) in the sun? What if the intrepid explorer is exploring? i.e., traveling, and can’t lay the device out in the sun? And what happens on a cloudy day? And how does the water get to be drinkable? Once it has been absorbed (or adsorbed, depends on the desiccant) by the desiccant, there will remain traces of that desiccant after separating water from desiccant. So now add a filter to the apparatus that needs lugged? So I’m not pooh-poohing the concept all the way back to the drawing board, but…

“If the production capacity of the device can be increased, Wang’s research could have a tangible impact…”

sounds like a serious understatement.

Vote Up0Vote Down

July 24, 2018 5:09 pm

dodgy geezer

Not a new idea by any means, but they’ve probably optimised it a bit. Might be useful for expeditions and rescues, but there’s not enough water in the air to run anything bigger…

Vote Up0Vote Down

July 23, 2018 9:45 am

Ellen

In a similar vein, think “solar energy”. It’s a fool’s idea to try to run an industrial society with it. But every time I travel, I see solar batteries performing useful work. They sit on traffic signs, pointing South, charging batteries to power “Attention!” lights blinking on the signs. Or whatever other low-power use that would otherwise have to be connected up to a power line or need battery replacements every now-and-then.

Sort of like running a water pipe or a water-carrying truck to a place in the middle of a desert.

Vote Up3Vote Down

July 23, 2018 10:56 am

Killer Marmot

Yes, there are desert tribes who have collected moisture from the night air for centuries, and probably millennia. Articles on scientific breakthroughs sometimes fail to acknowledge preceding technologies.

Vote Up2Vote Down

July 23, 2018 11:05 am

rocketscientist

They’ve been doing this on Tatooine for eons, but that was a long time ago…

Vote Up3Vote Down

July 23, 2018 7:51 pm

DaveK

…and far, far away.

Vote Up0Vote Down

July 24, 2018 3:39 pm

Red94ViperRT10

Not to mention on Arrakis. I gathered that was far in the future, but still far, far away.

Vote Up0Vote Down

July 24, 2018 5:20 pm

Philip

1kg of their material pulled 250cc of water out of the air over 24hrs.
In a temperate climate, water intake is (recommended) 2.5L/day.

Thats about 10kg of material – hardly portable, and this is for only one person.
My guess is that if you put four (for a normal western family) side by side, you won’t get anything like 250cc/day out of them. They will need to be widely spaced.

Move out into an hot, arid climate and water needs increase. So you are probably looking at 20kg per person.

Then there is the camel … or two … or three

This is interesting, and a fan to move the air might improve things, but I don’t think its really an answer.

Vote Up2Vote Down

July 23, 2018 9:51 am

Peta of Newark

We’re missing something here.
There are any number of ‘magic powders’ that will pull water out of thin air, sodium or calcium chlorides, silica gel, almost any ‘nitrate’ but, fair doings, they do rather have drawbacks.

What is missing is the magic step where the vapour extracted from the powder ‘is condensed’
How?
How does this condensation happen – don’t you need a cold surface?
What makes the cold surface?

Why even bother with the magic powder – why not just condense water vapour straight out of the air onto the cold surface and not bother with the powder?
Why not simply use an air-conditioner, or leave the door open on your fridge/freezer?
Why not use a Peltier Cooler – all solid state and can be powered by any old solar panel directly?

And this is where I get into real trouble, when I note that A Girl has invented this.
Why not use ‘A Boy’ – as in – Male Of The Species to find the water.

Like girls have a ‘social gene’ – a 6th sense if you like, so do boys.
Except theirs is the ability to sense the presence of water when not immediately obvious.
Under the dirt. Water divining.
(Everybody cracks up laughing)

Maybe go walkabouts an original Aborigine person – if there are any left on this world.
Think. Where did we evolve? A fairly hot & dry place. yes/no
Would not the ability to ‘sense water’ be One Fantastically Useful Thing for people who were hunters and may/would be required to track/follow animals they had shot/injured/poisoned across big expanses of open/unknown country. Possibly for days.

Water is key. So, dig a hole into some damp dirt and put a transparent cover over it. The trick of course being, knowing where the damp dirt is under a foot or so of bone-dry hot sand.
Is that why ‘we’ were successful and others were not

(What are all those fins and pipes under the condensation chamber in the video?
Is that a Peltier Cooler…..)

Vote Up1Vote Down

July 23, 2018 9:56 am

jorgekafkazar

The answers to your questions require a certain amount of non-verbal communication, AKA hand-waving, in lieu of facts or data. First, you must educate yourself in hand-wavingology. I’d suggest starting with this video where two scientists demonstrate how the concept can be explained and clarified:

Vote Up2Vote Down

July 23, 2018 11:37 am

Ben of Houston

Quarter-Liter of water per day? A CUP of water per DAY! Per KG of absorbent?
My cheap, Home Depot dehumidifier makes ~20 gallons a day if I can empty it whenever it fills up, and it weighs a significant amount less.

I also note that there was no mention of how much solar panel space this requires for the purge functions and the fans. I would be shocked if it’s a rational amount.

Finally, to quote Samuel L. Jackson (in character as Frozone), “There is No Water In The Air”. Most drought-stricken places have far less than 20% humidity.

Vote Up0Vote Down

July 23, 2018 10:09 am

MarkW

I’ve been researching de-humidifiers recently, and most of them are in the 30 pint per day range. That’s a bit less than 2 gallons.

Vote Up1Vote Down

July 23, 2018 12:49 pm

John Bell

It will have trouble going from small curiosity to practical application, I bet it never gets out of the lab. There have been other such attempts, they all flop.

Vote Up1Vote Down

July 23, 2018 10:10 am

DaveK

Have you no imagination or faith in the ability of a “girl” to invent something revolutionary?

Why, she could be the next Elizabeth Holmes!

What? Oh….

Never mind.

Vote Up0Vote Down

July 24, 2018 3:43 pm

John Bell

There was another one, claiming to condense water underground, from air, here is the web site, it is a crock of bull.https://www.waterseer.org

Vote Up0Vote Down

July 23, 2018 10:16 am

jorgekafkazar

How big a crock? What is it in Manhattans?

Vote Up2Vote Down

July 23, 2018 11:44 am

Kaiser Derden

water stills have been around for hundreds of years … this is just a new costly way to do it … interesting experiment though … but anyone living in dangerously arid conditions needs to move not buy this …

Vote Up1Vote Down

July 23, 2018 10:16 am

Bruce Cobb

So, 33 pounds of the mystery powder could produce about 1 gallon of water per day. Be still, my beating heart.

Vote Up0Vote Down

July 23, 2018 10:18 am

Barbee

Crop irrigation in remote areas? If affordable, I’d use it on my melons and sweet potatoes. Sweet!

Vote Up-1Vote Down

July 23, 2018 10:28 am

RayG

What is the material used to desiccate the air? What are the production issues? Is it, horrors, carbon-based, derived from hydrocarbons? Is the manufacturing process green, sustainable, renewable? How many Kw per unit of product? Just a few of the questions.

Vote Up1Vote Down

July 23, 2018 10:43 am

Myron Mesecke

We know that cutting down trees made the air around Mt. Kilimanjaro less humid. Which led to fewer clouds and less snow. Not enough snow to replenish the glacier ice lost due to sublimation.

Just weeks ago a study reported that urbanization in part of California removed enough vegetation that the air there also lost humidity. Not only did this also result in fewer clouds, but fewer clouds and less humidity is making it harder to fight wildfires in that area.

Then there is the report about the Baobab trees in Africa and how the oldest of them are dying. We know that many in Africa depend on open fires because they do not have access to other forms of energy. Reports state that areas are rapidly being stripped of trees and brush by people using it for firewood. Could a drop in humidity from vegetation loss be a cause of stress to Baobab trees?

Now we are supposed to suck humidity even more humidity from the air?

Vote Up0Vote Down

July 23, 2018 11:00 am

Tom in Florida

It’s probably better to just tow a couple of large ice bergs from the Arctic to where ever they are needed.

Vote Up1Vote Down

July 23, 2018 1:01 pm

Red94ViperRT10

Antarctic. All those “…multiple-Manhattans…” icebergs are in Antarctica.

Vote Up0Vote Down

July 24, 2018 5:33 pm

Robert of Texas

This device, in a single stroke, solves the Global Warming crisis. Pull enough of the greenhouse gas H2O out of the air and you will definitely lower temperatures… So now we can add CO2 into the atmosphere without any worry. Simply Genius! (/Sarc)

At the extraction rate they have, I see no use for this proof of concept. Too bulky and heavy to be of much use, and no indication of cost per liter of water formed (I assume materials will need to be replaced over time). The cooling process to condense the water is also left unexplained – using electricity to cool the device?

At the current efficiencies, you would need 2.5 (Liters per day) x 4 (1 quarter cup per kilogram) = 10Kg of material per person just to provide drinking water.

Vote Up1Vote Down

July 23, 2018 11:32 am

Kasuha

I am always VERY skeptical about such inventions. You need a LOT of air processed to get even small amount of water, and you need a LOT of energy to turn that vater from vapor to liquid. There are physical limits to that thing.
I’m no fan of Thunderf00t and his videos but here he at least calculates the amounts needed for similar (in this case obviously scam) project:https://www.youtube.com/watch?v=LVsqIjAeeXw
There were serious projects that tackled the topic and they all failed to get widespread because the yield was too small. Some of them still work, though. You can even pay them a visit and check the facts in place.https://en.wikipedia.org/wiki/Air_well_(condenser)

Vote Up0Vote Down

July 23, 2018 11:34 am

Peter Morris

I’m sorry there must be an error in translation.

250 mL per kg of powder per day?!? As in, about a half pint? Per 2.2 pounds of that powder?

Cancel whatever grant she had and just use the money to ship bottled water there.

Vote Up2Vote Down

July 23, 2018 11:43 am

Michael S. Kelly, LS, BSA, Ret.

I would imagine the “magic powder” is a molecular sieve such as sodium aluminosilicate based zeolite. These are FDA approved as food additives to prevent caking. They adsorb about 20% of their own weight in water, and can be regenerated by heating in a vacuum at temperatures from 175 to 315 C. The latter is the tricky part. Solar energy can certainly be used to heat the stuff, but the vacuum part is a little more exotic. At least the condensing part would be fairly easy, with such a high vapor temperature – even in a desert.

Vote Up0Vote Down

July 23, 2018 11:46 am

James

Great, one more dehumidifier scam. I bet you top dollar that a simple low tech rain harvesting system, IE, the roof, would cost a hundred times less and produce 100 times as much water.

Vote Up0Vote Down

July 23, 2018 12:05 pm

Alan Watt, Climate Denialist Level 7

Shades of Dune. So once you pull water vapor out of the air, you can then re-evaporate it and get cooling without using electricity. Where can I get some of this magical powder?

Vote Up0Vote Down

July 23, 2018 12:26 pm

Craig

Could “still suits” be just around the corner?

Vote Up0Vote Down

July 23, 2018 1:23 pm

Donald Kasper

Oh yum, water with chemical absorbant leeched in it. Could not possibly be carcinogenic.

Vote Up0Vote Down

July 23, 2018 12:29 pm

Donald Kasper

Wow, talk about mold problems. Assuming in deserts, it is not clogged by dust.

Vote Up0Vote Down

July 23, 2018 12:32 pm

Donald Kasper

The implication is the absorbant is a one-way street and won’t absorb moisture out of the box and release it into the atmosphere.

Vote Up0Vote Down

July 23, 2018 12:37 pm

Wiliam Haas

I would think that you could do this without the desiccant powder. Many refrigeration type air coolers are also dehumidifiers and pull water from the air. Powering these systems via solar panels is straight forward. I have a little window air conditioner and the instructions say that is important to tilt the unit so that the condensed water does not drip into the room. The air conditional in my car also pulls water form the air. I notice it dripping when I part the car on my driveway. What is so wonderful about what they are doing compared to what is already on the market?

Vote Up0Vote Down

July 23, 2018 12:40 pm

Michael S. Kelly

Yes, I have to agree that is a much better solution.

Vote Up0Vote Down

July 24, 2018 5:35 pm

Dave Anderson

This isn’t the first time this has come up.

Vote Up3Vote Down

July 23, 2018 12:47 pm

John Bell

Great debunking of Zero Mass Water solar powered water maker.

Vote Up1Vote Down

July 23, 2018 4:23 pm

Tom in Florida

The headline is wrong. It should read “New device from MIT pulls grant money out of thin air”

Vote Up11Vote Down

July 23, 2018 12:57 pm

Dennis Kuzara

Another way to get solar produced water: Bradford watermelons

Plus, our watermelon seeds provide a simple crop to cultivate which gives the people a huge, delicious melon full of naturally purified water.

Our mission: to drill fresh water wells all over the world and provide medication to treat waterborne illnesses.

My family and I prayed for guidance on how to use this family treasure in an amazing way that would bring God glory and have great impact in the world. One Sunday morning in church our pastor was sharing about a mission to drill fresh water wells in Africa. He shared a statistic that floored me. Every day around the world over 3000 people die of illnesses from poor drinking water, many of them are small children. That’s one person every 30 seconds. Most can be cured with a 30 cent pill. I imagined one of those grieving mothers losing her precious child. I imagined how painful it would be to lose one of my children that way. Unbearable. Unconscionable. That instant Watermelons for Water was conceived.

We have already seen results! Watermelon sales have provided funding for the drilling of fresh water wells in Tanzania and Bolivia. Plus, our watermelon seeds provide a simple crop to cultivate which gives the people a huge, delicious melon full of naturally purified water.

They did that in India then had to go back and tell people not to use them due to high arsenic content of water from the wells. I hope you test yours.

Vote Up0Vote Down

July 26, 2018 11:57 pm

John F. Hultquist

When a cup of the powder produces a gallon of water per hour for under 50 cents, have them send me one and I’ll test it for a year and write a review.
How well does it work at -10°F ?

Vote Up0Vote Down

July 23, 2018 2:00 pm

Ve2

Been there, done than.

DUNE.

Vote Up0Vote Down

July 23, 2018 2:04 pm

Red94ViperRT10

But in Dune, the still suit collected the moisture out of their breath, and recycled the sweat from their skin. While the method of filtration/processing was left out (it is, after all, a FICTION book!), at least it wasn’t creating water that didn’t exist.

Vote Up0Vote Down

July 24, 2018 6:12 pm

Craig from Oz

Moisture farming?

I had an Uncle Owen who was into that back in the 70s… 🙂

Vote Up2Vote Down

July 23, 2018 4:09 pm

Raymond Belanger

And you get mushrooms too… great!

Vote Up0Vote Down

July 23, 2018 9:11 pm

Johann Wundersamer

“Keeping costs low and efficiency high is one of Wang’s central goals. “We hope to develop a device that provides relief to the millions of people living in communities that lack the infrastructure needed to provide access to clean drinking water”

Water for millions – in arid conditions. Wait and see.

Vote Up0Vote Down

July 23, 2018 5:19 pm

Holly Birtwistle

Developing nations need infrastructure for water just like developed nations have. We don’t use solar stills in Arizona do we? No, water is collected from distant sources and distributed where it is needed. This is a typical scheme out of academia ‘ to help’ those disposable people in developing nations without putting the planet at risk by ‘ using too much water’. Of course, the academics can use as much water as they want as they live in a developed nation. Sounds like the other ‘ solutions’ for the developing nations rolled out by the wizards of oz in academia, like improved apparatus for burning dung, instead of fossils to make electricity. What did Ehrlich day? “ Giving humanity affordable energy would be like giving a child a loaded gun’ or something to that effect. But Erhlich lived with affordable
Energy and sacrificed nothing. The ‘masses’ simply aren’t intelligent enough to determine future. Such is the ideology of a Marxist/Environmentalist. In other words, a Globalist. Weren’t solar stills first intended for space travel?

Vote Up0Vote Down

July 23, 2018 5:24 pm

Patrick MJD

Hasn’t this “technology” been around for hundreds of years, a solar still/condenser?

Vote Up0Vote Down

July 23, 2018 5:54 pm

DC Cowboy

No. A condenser doesn’t require ‘magic pixie dust’ to produce water.

An air conditioner accomplishes the same effect.

Vote Up1Vote Down

July 23, 2018 7:48 pm

DC Cowboy

A quarter-liter of water per day per kilogram of the absorbent powder.” How much does the powder cost?

From the description it doesn’t seem like the powder is a catalyst and is consumed in the water process?

.25 liters of water/day/kilo of powder doesn’t seem like a very efficient process to me. A kilo is roughly 2.2lbs. So, to produce 1,000 liters (264 gallons) of water/day you’d need 8,800 lbs (4+ tons) of this ‘powder’. If it is is consumed in the process I don’t see it as being in the least practical.

Vote Up-1Vote Down

July 23, 2018 7:46 pm

wesley bruce

Hitch a commercially available air well up to a solar cell on the roof and you get more than a quarter litre per unit volume of condenser surface. Add a battery pack so it runs at night when less work is needed to extract the humidity and you may have a winner. Still is is progress. The catch is zerolite volume and surface area is not the most power hungry thing the fans are.
I’m working on a farm air well. That’s harder but could work using a ground loop system. I really need a lab.

Vote Up1Vote Down

July 23, 2018 8:59 pm

ironargonaut

How much does a hole and a plastic sheet produce in same environment? That’s a survival trick for those wondering what I’m blathering about.

Vote Up0Vote Down

July 24, 2018 12:26 am

Earthling2

I have been collecting 2-3 litres of water dripping out my RV AC in the desert for many years. Especially productive at night when relative humidity is a lot higher. If I drink it, I gravity filter it for safety although I generally boil this water for my pot of coffee in the morning.

But really nothing new here…even the magic powder has been available for years as a dehumidifiing agent in the RV industry, for when you park your RV and want to ensure lower humidity in a certain area, such as those little packaging pellets that absorb moisture. What will be interesting is if they can drastically increase the efficiency of this process for a potable water supply. It would be a useful emergency back up to have in a very dry environment to ensure some drinking water to stay alive. Obviously, this isn’t proposed for any industrial sized water supply for more than pure drinking water and then only where getting a sufficient water source is already a challenge. So, if a 500 ml water bottle is with a buck, this might be worth a shot. Or more if you are dying of thirst in the desert.

Vote Up0Vote Down

July 24, 2018 2:12 am

Pat Frank

Their “powder” is probably a zeolite. Zeolites can absorb quite a bit of water without any change in volume. The water can be baked out again, and the zeolite can be re-used.

So, likely they have a zeolite that absorbs 10% its weight in water (1 kg produces 250 gm of water). The copper condensation stage might be a Peltier cooler, driven by solar power.

It’s a nice experiment, but one doubts it will ever produce useful amounts of water. Perhaps it could be an emergency water back-up for one person who is desert-bound.

EXPLETIVE ! EXPLETIVE ! EXPLETIVE !
This reads : HAVE WEIRD AND WONDERFUL CONCEPT !
SHOULD EARN ME another PhD ( in wishful thinking at least ! )
NOW…..YOU GUILT-RIDDEN , DESCENDANTS OF SLAVE OWNERS , RACIST , HOMOPHOBIC ,
SEXIST BIGOTS………….SEND ME LARGE SUMS OF MONEY TO ASSUAGE YOUR GUILT NOW !
You have been warned !!
.
God spare us ! It is a concept at a very basic level and entirely unsuitable for anything
except use in a laboratory ! Perhaps she can audition for “STAR TREK” THE RETURN !

Vote Up-1Vote Down

July 24, 2018 9:39 am

Dan Evens

I’m not believing the claims. To condense water you need to pull heat out of the vapor. There’s no getting around it. You can’t fool thermodynamics. Where are you going to put the heat? The vid shows some kind of device under the little glass box. What’s that?

Vote Up1Vote Down

July 24, 2018 12:07 pm

Red94ViperRT10

Actually, it’s worse than that. I just reviewed the video again. First, they expose the desiccant to air, it absorbs moisture, until saturated or until time is up, whichever comes first, I guess. THEN, to separate the moisture from the desiccant, you must apply heat. So this is not a continuous process, this is more like mammalian lungs, inhale, absorb oxygen and give of CO2, exhale, repeat. So the same with this thing. And it’s not even the same chamber, apparently. (I suppose the final design could include some bells and whistles so that the desiccant absorbs (or adsorbs, I’m not sure of the desiccant) until sensors say it has hit a limit, valves close and switches close, etc…) Then the wafer is taken from the lung and put into a pressure vessel/condenser, where heat is applied to the wafer (no explanation where this energy comes from, the press release says it can come from the sun, but the video glosses right over that) and the moisture condenses out (the video switches to graphics here, we have no clue if this is a real process or completely CGI). So I can picture constructing the “…engineered matrix…” with an element already in it. Apply power and presto, voilá! the moisture comes out of the wafer and condenses. Here, I see a jug, possibly copper, with a high-emissivity outer coating (flat-black paint) that can radiate to the night sky and cool enough to condense the moisture. But it they’re going to derive ALL the power this sucker needs from just sunlight, now you have a 3-step process, 1) move air over the desiccant and desiccate moisture out of the air 2) move the desiccant to another chamber and heat it to release the moisture 3) remove the wafer, (or keep heating it in place so it doesn’t recombine with the moisture), and cool the chamber ’til the moisture condenses. So an external solar panel to provide electricity to the element, with the condensing chamber in the bottom of a tube so the chamber can radiate to space, while shaded from the sun? Or heat during the day, then remove the desiccant (or isolate it with valves) and condense at night? A very unwieldy process, either way. And I would still want my drinking water filtered, not to mention cooled to below bathwater temperatures. Like I said above, not ready for prime time.

Vote Up0Vote Down

July 24, 2018 6:44 pm

ATheoK

“During a field test in Tempe, Arizona earlier this year, a small proof-of-concept prototype of the device extracted a quarter-liter of water per day per kilogram of the absorbent powder. The researchers hope to increase this output by further tailoring the powder and optimizing the device.

If the production capacity of the device can be increased, Wang’s research could have a tangible impact in places experiencing water scarcity — even in the driest of conditions.”

“the device extracted a quarter-liter of water per day per kilogram of the absorbent powder.”

How trite!?
250 grams of water in exchange for 1,000 grams of an unnamed substance…

And those especially dry environments will simply love devices that dry the atmosphere to supply drinking water…

Reminds me of a series of stories; Dune!”

Meanwhile, all of those native creatures that evolved to eke out existence in dry environments will simply need to do better.

Nor have these simpletons discussed what happens to temperatures when atmospheric water content levels are substantially dessicated.
I guess, they have to design more effective CO₂ to make up for water vapor losses.

Vote Up0Vote Down

July 24, 2018 2:37 pm

Gamecock

If they want to keep cost down, and triple the output, run it on electricity. Using solar is a gimmick. It raises cost and severely limits how long it can run each day.

Vote Up0Vote Down

July 24, 2018 6:31 pm

jon spencer

Another one?
Seems like there is a article touting these about twice a year.
Without trying hard I found articles showing machines of this type from 2005 and onward.

We use cookies to ensure that we give you the best experience on WUWT. If you continue to use this site we will assume that you are happy with it. This notice is required by recently enacted EU GDPR rules, and since WUWT is a globally read website, we need to keep the bureaucrats off our case!OkPrivacy policy